lib: Replace shim IPCPs with points of attachment

Removes the UDP and Ethernet shim IPCPs. The unicast and broadcast
IPCPs can now directly attach to a "legacy" socket. We adopt Saltzer's
Point-of-Attachment terminology, also advocated in Day's "Patterns in
Network Architecture". The "poa" component manages these
PoA's with one management thread, one link monitoring thread and one
thread per attached point.

For Ethernet PoA's the irm connect and enroll can resolve the
destination IPCP or Layer name with a broadcast name query over the
attached PoAs (first reply wins). UDP PoA's require a destination IP
address or FQDN.

attach to a local endpoint (required both server and client side):

 irm ipcp poa attach name a udp 10.0.0.1
 irm ipcp poa attach name a udp 10.0.0.1:3435
 irm ipcp poa attach name a udp [::1]:3435
 irm ipcp poa attach name a eth dev eth0
 irm ipcp poa attach name a eth dev eth0 ethertype 0xA000

release a PoA (refused while it carries a flow):

 irm ipcp poa detach name a udp 10.0.0.1:3435
 irm ipcp poa detach name a eth eth0

list an IPCP's PoAs:

 irm ipcp poa list name a

connect to a peer, by name or at an address:

 irm ipcp connect name b dst a
 irm ipcp connect name b dst a eth
 irm ipcp connect name b dst a eth dev eth0
 irm ipcp connect name b dst a udp 10.0.0.1:3435
 irm ipcp connect name b dst a udp peer.example.com:3435

disconnect by peer name, no address:

 irm ipcp disconnect name b dst a
 irm ipcp disconnect name b dst a component mgmt

enroll has the same shape as connect:

 irm ipcp enroll name b layer lr autobind
 irm ipcp enroll name b layer lr autobind eth dev eth0
 irm ipcp enroll name b layer lr autobind udp 10.0.0.1:3435

the IRMd config file attaches PoAs and names peers the same way:

 udp = [ "10.0.0.1", "10.0.0.1:3436" ]
 eth = [ "eth0", {dev="eth1", ethertype=0xA007} ]

 enrol={dst="LAN", eth={dev="eth0"}}
 conn=[{dst="lan3", eth={}}, {dst="lan4", udp="10.0.0.1:3435"}]

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

2 files changed, 10 insertions, 7 deletions

diff --git a/src/ipcpd/unicast/fa.c b/src/ipcpd/unicast/fa.c
index 596b101b..744eb316 100644
--- a/src/ipcpd/unicast/fa.c
+++ b/src/ipcpd/unicast/fa.c
@@ -130,8 +130,8 @@ struct fa_flow {
         size_t   u_snd;    /* Flow updates sent              */
         size_t   u_rcv;    /* Flow updates received          */
 #endif
-        uint64_t s_eid;  /* Local endpoint id                */
-        uint64_t r_eid;  /* Remote endpoint id               */
+        uint64_t s_eid;  /* Local PoA id                     */
+        uint64_t r_eid;  /* Remote PoA id                    */
         uint64_t r_addr; /* Remote address                   */
         void *   ctx;    /* Congestion avoidance context     */
         uint64_t fair;   /* SFQ virtual finish tag (bytes)   */
@@ -208,8 +208,8 @@ static int fa_rib_read(const char * path,
         sprintf(buf,
                 "Flow established at:             %20s\n"
                 "Remote address:                  %20s\n"
-                "Local endpoint ID:               %20s\n"
-                "Remote endpoint ID:              %20s\n"
+                "Local PoA ID:               %20s\n"
+                "Remote PoA ID:              %20s\n"
                 "Sent (packets):                  %20zu\n"
                 "Sent (bytes):                    %20zu\n"
                 "Send failed (packets):           %20zu\n"
diff --git a/src/ipcpd/unicast/main.c b/src/ipcpd/unicast/main.c
index 86cb1f06..3ee53401 100644
--- a/src/ipcpd/unicast/main.c
+++ b/src/ipcpd/unicast/main.c
@@ -35,6 +35,7 @@
 #include <ouroboros/ipcp-dev.h>
 #include <ouroboros/logs.h>
 #include <ouroboros/notifier.h>
+#include <ouroboros/qos.h>
 #include <ouroboros/random.h>
 #include <ouroboros/rib.h>
 #include <ouroboros/time.h>
@@ -175,12 +176,14 @@ static void stop_components(void)
         ipcp_set_state(IPCP_BOOT);
 }
 
-static int unicast_ipcp_enroll(const char *        dst,
-                               struct layer_info * info)
+static int unicast_ipcp_enroll(const char *            dst,
+                               const struct poa_addr * addr,
+                               struct layer_info *     info)
 {
         struct ipcp_config * conf;
         struct conn          conn;
         uint8_t              id[ENROLL_ID_LEN];
+        qosspec_t            qs = qos_msg;
 
         if (random_buffer(id, ENROLL_ID_LEN) < 0) {
                 log_err("Failed to generate enrollment ID.");
@@ -189,7 +192,7 @@ static int unicast_ipcp_enroll(const char *        dst,
 
         log_info_id(id, "Requesting enrollment.");
 
-        if (connmgr_alloc(COMPID_ENROLL, dst, NULL, &conn) < 0) {
+        if (connmgr_alloc(COMPID_ENROLL, dst, &qs, addr, &conn) < 0) {
                 log_err_id(id, "Failed to get connection.");
                 goto fail_id;
         }